Pd Nanoparticles/F, N Codoping Graphene Composites for Oxygen Reduction and Zinc-Air Batteries

The electrocatalytic activity is closely associated with the electronic structure of catalysts. Electron-deficient palladium (Pd) has been proved to show better oxygen reduction reaction performance than the electrophilic one due to the downshift of the d-band center. In this work, Pd nanoparticles are uniformly dispersed in F, N-doping graphene with the assistant of silicon nanowires and hydrofluoric acid (Pd/F, N-doping G). A strong interaction between the metal and doped-graphene leads to the electron-deficiency of the modified Pd, which is beneficial for obtaining proper adsorption energy of oxygen species. The as-prepared Pd/F, N-doping G-3 catalyst shows a four-electron oxygen reduction pathway with large half-wave potential of 0.87 V and high onset potential of 0.99 V in 0.1 M KOH. In addition, the Pd/F, N-doping G-3 based zinc-air battery exhibits an open potential of 1.40 V and a high power density of 229 mW·cm–2.